U.K. Foreign Secretary William Hague said Tuesday that economic reforms in Ukraine remain a precondition to emergency loans.

WASHINGTON—U.K. Foreign Secretary William Hague said Tuesday that economic reforms in Ukraine remain a precondition to emergency loans, acknowledging a difficult calculus that confronts Western officials as they grapple with options for rescuing the near-failing state.

U.S., European and International Monetary Fund officials are seeking to assemble an international financing package for Kiev that both encourages a pro-Western...